Patent GB-683545-A (GB)
Title: Improvements in machines for metal turning, screwing and like operations
IPC: B23G1/04
Filed: 1950-02-21
Abstract: 683,545. Lathes; straightening. DORIN, A. Feb. 21, 1951 [Feb. 21, 1950], No. 4408/50. Classes 83 (iii) and 83 (iv). A machine for metal turning and like operations of the kind in which the tools revolve about the axis of the stationary work, comprises a headstock having a hollow main spindle surrounding a stationary sleeve through which the stock is advanced by a feed-slide mounted at the rear end of the machine, the spindle being driven externally and having at its forward end a toolhead or carrier plate. A number of cams, arranged on one or more cam-shafts below the headstock, are so.arranged that the cams control the engagement of the feed-slide with the work and the advance and return of the feedslide as well as the holding of the work and the movement of the tools. The machine comprises a base 11, Fig. 1, and an electric motor 13 driving a shaft 14 from which a cone pulley arrangement controlled from a belt shifter 17 transmits a drive to a head-stock spindle via a pulley 21. The shaft 14 also drives through pulleys 16, 19, a worm gear enclosed in a housing 20 from which drives are transmitted to camshafts 45, 34, through pick-off gears 58. The latter may be disengaged by a lever 50 to permit hand-cranking of the cam-shafts for setting-up. The main spindle 23 rotates within the headstock and carries at one end a rotating tool-head 86 with one or more pairs of radially adjustable tools which are connected with balance weights 88, Fig. 7, to overcome the effect of centrifugal force. The tools are automatically fed by a wedge 91, Fig. 3, moved axially by a sleeve 92 from a cam 95 on shaft 34 operating a lever connected to the sleeve. A stationary tube 24 within the headstock spindle carries a reciprocable sleeve 25 with a collet 36 at its forward end for gripping the stock. A cam 37 operating through a lever 38 and collar 39 moves the sleeve 25 to grip the stock. At the same time, an edge cam forming part of cam 37 operates gripping fingers in a stationary work-gripping member 35 to hold the rear end of the stock. The latter is supplied from a reel (not shown) and passes through straightening rollers 28, 29 carried on a feed-slide 26. This slide is provided at its forward end with a cam-operated gripping device 30 which closes on the stock for a forward feed movement. Movement of the feed slide is obtained from a cam 44 on the shaft 45 acting through a lever 40 with an adjustable fulcrum so that different lengths of stock may be fed. The straightening device may be separate from the feed slide, and turning operations may be performed on the stock while it is moving through the cutter head. Attachments for drilling, screwing, &c.-An attachment for centring, drilling and screwthreading or tapping, comprises a base 100, Fig. 8, which may be secured to the left-hand side of the machine, Fig. 1. The main drive to the attachment is from shaft 18 through V-belts to a shaft 107 in the attachment and the main cam-shaft 45 is coupled to an auxiliary camshaft 133 on the attachment. Three tool spindles 102-104, Fig. 9, are provided in a head 101 which pivots about the axis of a pulley shaft 117 to bring the tools into line with the stock in the main machine. Means are provided for bringing the tools into line in turn and feeding them automatically. The third spindle 104 is driven at slow speed for tapping and a high speed reverse is incorporated in the drive.